The mathematica guidebook for numerics

1: Numerical computations

Approximate numbers

Fitting and interpolating functions

Compiled programs

Linear algebra

Fourier transforms

Numerical functions and their options

Sums and products

Integration

Solution of equations

Minimization

Solution of differential equations

Two applications

2: Computations with exact numbers

Divisors and multiples

Number theory functions

Combinatorial functions

Euler, Bernoulli, and Fibonacci numbers.